This research was carried out with the aim of obtaining appropriate principles for describing the influence of working parameters and the aggressive action of an acidic medium on the wear and corrosion resistance of martensitic stainless steels. Tribological tests were performed on induction-hardened surfaces of stainless steels X20Cr13 and X17CrNi16-2 under combined wear conditions at a load of 100 to 300 N and a rotation speed of 382 to 754 min⁻¹. The wear test was carried out on a tribometer with the use of an aggressive medium in the chamber. After each wear cycle on the tribometer, the samples were exposed to corrosion action in a corrosion test bath. Analysis of variance revealed a significant influence of rotation speed and load due to wear on the tribometer. Testing the difference in the mass loss values of the samples due to corrosion using the Mann–Whitney U test did not show a significant effect of corrosion. Steel X20Cr13 showed greater resistance to combined wear, which had a 27% lower wear intensity compared to steel X17CrNi16-2. The increase in wear resistance of X20Cr13 steel can be attributed to the higher surface hardness achieved and the effective depth of hardening. The mentioned resistance is the result of the creation of a martensitic surface layer with dispersed carbides, which increases the resistance to abrasion, dynamic durability, and fatigue of the surface of the protective layer.

Photovoltaic industry has displayed an exponential expansion rate over the past two decades. Currently, 1185 GW of the global electricity demand is derived from photovoltaic (PV) panels with more to come in the next two decades. With the growing installment rate, a concern regarding managing panels that reached the end of their life-span grows. Despite the fact that the approximate life-span of a panel is 25 years, oftentimes this interval is shortened due to weather conditions, low-quality installations, and poor maintenance. Therefore, a global attention is focused on research and law-regulation of proper recycling and disposal of the PV waste. In this contribution, recyclability of one PV panel is determined upon subjecting it to the simplest recycling process, which is manual mechanical separation using common hand-tools. In addition, an ecological-economic analysis of the panel, which yields an absolute profit of the panel is presented.

Batteries as a power source are the basis for all major hand tool manufacturers as vide variety of portable products became battery powered for more convenient usage. Manufacturers disable unapproved battery applications in their products by designin...